Flooring: laminate packs, carpet and underlay
Laminate and click vinyl are sold in packs that cover a fixed area, usually printed on the end of the pack. A 4 x 3.5 m room is 14 m²; with 10% for cuts you need 15.4 m², which is 7 packs of 2.22 m². Simple rooms laid straight can use less allowance; herringbone and rooms with many corners need more.
This page brings together our UK flooring calculators and guides: laminate and LVT, carpet bought off the roll, underlay, beading and skirting.
Packs of laminate by room size
For packs of 2.22 m², worked out by the laminate calculator. Check the coverage on your pack, which varies by product.
| Room (metres) | Floor area (m²) | Buy with 5% | Buy with 10% | Packs at 10% |
|---|---|---|---|---|
| 3 x 2.5 | 7.5 | 7.9 | 8.3 | 4 |
| 3 x 3 | 9.0 | 9.5 | 9.9 | 5 |
| 4 x 3 | 12.0 | 12.6 | 13.2 | 6 |
| 4 x 3.5 | 14.0 | 14.7 | 15.4 | 7 |
| 5 x 4 | 20.0 | 21.0 | 22.0 | 10 |
| 6 x 4 | 24.0 | 25.2 | 26.4 | 12 |
Laminate and click vinyl
Floating floors need underlay (unless it is attached), a 10 mm expansion gap at the walls hidden by beading or skirting, and threshold bars at doorways. The materials list counts all of it from the room size.
Carpet
UK carpet comes off 4 m and 5 m wide rolls, so you buy a length of the whole width and pay for the offcut. A 4.5 x 3.2 m room is 14.4 m², but using a 5 m roll you buy 16.5 m², with 14.6 m of gripper around the walls.
Skirting
New floors often mean new skirting, or at least beading to cover the expansion gap. The skirting calculator counts lengths from the room size less doorways.
Every calculator for this topic
Guides
- Common Mistakes Laying Laminate Flooring (UK): Packs and GapsLaminate mistakes: no waste, no expansion gap, no acclimatising. A 4 × 3.5 m room is 14 m² and takes 7 packs of 2.22 m² with 10% extra.
- How Much Carpet Do I Need? Rolls, Seams and Underlay (UK)A room 4.5 × 3.2 m needs 3.30 m from a 5 m roll. Charts for 4 m and 5 m rolls, seams, pattern repeats, underlay and gripper.
- Laminate, Vinyl (LVT) or Engineered Wood Flooring: Which?Compare laminate, luxury vinyl tile and engineered wood for a UK room: water, wear, underfloor heating and how many packs a 4 x 3.5 m room needs.
- How Much Skirting Board Do I Need? Lengths for a Room (UK)Skirting board needed = room perimeter less the doorways, plus 10%. A UK chart of lengths for rooms from 3×3 to 7×5 m, in 2.4 m, 3 m and 4.2 m boards.
- Laminate Flooring Materials List: Packs, Underlay, Beading (UK)What to buy for a 4 × 3.5 m laminate floor: packs of flooring with 10% waste, underlay, scotia or beading and door bars, with a chart for other rooms.
Other guides that use these calculators: How Much Plasterboard Do I Need? Sheets, Screws and Tape (UK) · Staircase Regulations UK: Rise, Going, Pitch and Number of Steps · How Many Tiles Do I Need? UK Guide with Adhesive and Grout · Stud Wall Materials List: Timber, Plasterboard, Screws (UK)
Answers for common sizes
Already know the size? These pages give the worked answer for one common size each, with the inputs filled in so you can adjust them.
Project planners
Planning the whole job rather than one material? These step-by-step planners put the calculators above in the order you will need them.
Frequently asked questions
How many packs of laminate for a 4 x 3.5 m room?
7 packs of 2.22 m², covering 15.4 m² with 10% for cuts on the 14 m² floor.
How much extra laminate should I buy?
About 10% for an ordinary room laid straight, 5% for a large simple room and 15% for herringbone or diagonal layouts.
Why does carpet cost more than the room size?
Carpet is cut from a 4 m or 5 m wide roll, so the width you buy is fixed and the offcut is paid for. Measure into door openings too.
Should I keep a spare pack?
Yes. Colours vary between batches, and a spare pack makes a damaged board easy to replace.
Related topics
Estimates only. Quantities depend on your materials, site and supplier, so check pack sizes and coverage on the label. Check the Building Regulations and any planning rules for anything structural or close to a boundary. How we calculate.